* Makefile.in (hogweed_SOURCES): Added dsa-sha1-sign.c,

dsa-sha1-verify.c, dsa-sha256-sign.c, and dsa-sha256-verify.c.

* dsa.h: Updated and added dsa declarations.

* dsa-sha256-verify.c (dsa_sha256_verify_digest): New file, new
function.
(dsa_sha256_verify): New function.
* dsa-sha256-sign.c (dsa_sha256_sign_digest): New file, new
function.
(dsa_sha256_sign): New function.

* dsa-sha1-verify.c (dsa_sha1_verify_digest): New file. Moved and
renamed function, from dsa_verify_digest, rewrote to use
_dsa_verify.
(dsa_sha1_verify): Analogous change, renamed from dsa_verify.
* dsa-sha1-sign.c (dsa_sha1_sign_digest): New file. Moved and
renamed function, from dsa_sign_digest, rewrote to use _dsa_sign,
and added return value.
(dsa_sha1_sign): Analogous change, renamed from dsa_sign.

* dsa-verify.c (_dsa_verify): New general verification function,
for any hash.
* dsa-sign.c (_dsa_sign): New general signing function, for any
hash. Returns success code, like the rsa signture functions.

Rev: nettle/ChangeLog:1.71
Rev: nettle/Makefile.in:1.22
Rev: nettle/dsa-sha1-sign.c:1.1
Rev: nettle/dsa-sha1-verify.c:1.1
Rev: nettle/dsa-sha256-sign.c:1.1
Rev: nettle/dsa-sha256-verify.c:1.1
Rev: nettle/dsa-sign.c:1.3
Rev: nettle/dsa-verify.c:1.3
Rev: nettle/dsa.h:1.4

9 files changed, 335 insertions, 59 deletions

diff --git a/ChangeLog b/ChangeLog
index 926cefb2..42a9f8ec 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,31 @@
+2010-03-30  Niels Möller  <nisse@lysator.liu.se>
+
+	* Makefile.in (hogweed_SOURCES): Added dsa-sha1-sign.c,
+	dsa-sha1-verify.c, dsa-sha256-sign.c, and dsa-sha256-verify.c.
+
+	* dsa.h: Updated and added dsa declarations.
+
+	* dsa-sha256-verify.c (dsa_sha256_verify_digest): New file, new
+	function.
+	(dsa_sha256_verify): New function.
+	* dsa-sha256-sign.c (dsa_sha256_sign_digest): New file, new
+	function.
+	(dsa_sha256_sign): New function.
+
+	* dsa-sha1-verify.c (dsa_sha1_verify_digest): New file. Moved and
+	renamed function, from dsa_verify_digest, rewrote to use
+	_dsa_verify.
+	(dsa_sha1_verify): Analogous change, renamed from dsa_verify.
+	* dsa-sha1-sign.c (dsa_sha1_sign_digest): New file. Moved and
+	renamed function, from dsa_sign_digest, rewrote to use _dsa_sign,
+	and added return value.
+	(dsa_sha1_sign): Analogous change, renamed from dsa_sign.
+
+	* dsa-verify.c (_dsa_verify): New general verification function,
+	for any hash.
+	* dsa-sign.c (_dsa_sign): New general signing function, for any
+	hash. Returns success code, like the rsa signture functions.
+
 2010-03-29  Niels Möller  <nisse@lysator.liu.se>
 
 	* configure.ac (ABI): Attempt to use a better, ABI-dependant,
diff --git a/Makefile.in b/Makefile.in
index 7315b2b3..d4c8f1b6 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -88,6 +88,8 @@ hogweed_SOURCES = sexp.c sexp-format.c \
 		  rsa-keygen.c rsa-compat.c \
 		  rsa2sexp.c sexp2rsa.c \
 		  dsa.c dsa-sign.c dsa-verify.c dsa-keygen.c \
+		  dsa-sha1-sign.c dsa-sha1-verify.c \
+		  dsa-sha256-sign.c dsa-sha256-verify.c  \
 		  dsa2sexp.c sexp2dsa.c \
 		  pgp-encode.c rsa2openpgp.c \
 		  der-iterator.c der2rsa.c der2dsa.c
diff --git a/dsa-sha1-sign.c b/dsa-sha1-sign.c
new file mode 100644
index 00000000..5654c493
--- /dev/null
+++ b/dsa-sha1-sign.c
@@ -0,0 +1,56 @@
+/* dsa-sha1-sign.c
+ *
+ * The original DSA publickey algorithm, using SHA-1.
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2010 Niels Möller
+ *  
+ * The nettle library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or (at your
+ * option) any later version.
+ * 
+ * The nettle library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with the nettle library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#if HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include "dsa.h"
+
+int
+dsa_sha1_sign_digest(const struct dsa_public_key *pub,
+		     const struct dsa_private_key *key,
+		     void *random_ctx, nettle_random_func random,
+		     const uint8_t *digest,
+		     struct dsa_signature *signature)
+{
+  return _dsa_sign(pub, key, random_ctx, random,
+		   SHA1_DIGEST_SIZE, digest, signature);
+}
+
+
+int
+dsa_sha1_sign(const struct dsa_public_key *pub,
+	      const struct dsa_private_key *key,
+	      void *random_ctx, nettle_random_func random,
+	      struct sha1_ctx *hash,
+	      struct dsa_signature *signature)
+{
+  uint8_t digest[SHA1_DIGEST_SIZE];
+  sha1_digest(hash, sizeof(digest), digest);
+
+  return _dsa_sign(pub, key, random_ctx, random,
+		   sizeof(digest), digest, signature);
+}
diff --git a/dsa-sha1-verify.c b/dsa-sha1-verify.c
new file mode 100644
index 00000000..73e948c1
--- /dev/null
+++ b/dsa-sha1-verify.c
@@ -0,0 +1,51 @@
+/* dsa-sha1-verify.c
+ *
+ * The original DSA publickey algorithm, using SHA-1.
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2002, 2003, 2010 Niels Möller
+ *  
+ * The nettle library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or (at your
+ * option) any later version.
+ * 
+ * The nettle library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with the nettle library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#if HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdlib.h>
+
+#include "dsa.h"
+
+int
+dsa_sha1_verify_digest(const struct dsa_public_key *key,
+		       const uint8_t *digest,
+		       const struct dsa_signature *signature)
+{
+  return _dsa_verify(key, SHA1_DIGEST_SIZE, digest, signature);
+}
+
+int
+dsa_sha1_verify(const struct dsa_public_key *key,
+		struct sha1_ctx *hash,
+		const struct dsa_signature *signature)
+{
+  uint8_t digest[SHA1_DIGEST_SIZE];
+  sha1_digest(hash, sizeof(digest), digest);
+
+  return _dsa_verify(key, sizeof(digest), digest, signature);
+}
diff --git a/dsa-sha256-sign.c b/dsa-sha256-sign.c
new file mode 100644
index 00000000..ea82022e
--- /dev/null
+++ b/dsa-sha256-sign.c
@@ -0,0 +1,55 @@
+/* dsa-sha256-sign.c
+ *
+ * The DSA publickey algorithm, using SHA-256 (FIPS186-3).
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2010 Niels Möller
+ *  
+ * The nettle library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or (at your
+ * option) any later version.
+ * 
+ * The nettle library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with the nettle library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#if HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include "dsa.h"
+
+int
+dsa_sha256_sign_digest(const struct dsa_public_key *pub,
+		       const struct dsa_private_key *key,
+		       void *random_ctx, nettle_random_func random,
+		       const uint8_t *digest,
+		       struct dsa_signature *signature)
+{
+  return _dsa_sign(pub, key, random_ctx, random,
+		   SHA256_DIGEST_SIZE, digest, signature);
+}
+
+int
+dsa_sha256_sign(const struct dsa_public_key *pub,
+		const struct dsa_private_key *key,
+		void *random_ctx, nettle_random_func random,
+		struct sha256_ctx *hash,
+		struct dsa_signature *signature)
+{
+  uint8_t digest[SHA256_DIGEST_SIZE];
+  sha256_digest(hash, sizeof(digest), digest);
+
+  return _dsa_sign(pub, key, random_ctx, random,
+		   sizeof(digest), digest, signature);
+}
diff --git a/dsa-sha256-verify.c b/dsa-sha256-verify.c
new file mode 100644
index 00000000..ed79a86e
--- /dev/null
+++ b/dsa-sha256-verify.c
@@ -0,0 +1,51 @@
+/* dsa-sha256-verify.c
+ *
+ * The DSA publickey algorithm, using SHA-256 (FIPS186-3).
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2010 Niels Möller
+ *  
+ * The nettle library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or (at your
+ * option) any later version.
+ * 
+ * The nettle library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with the nettle library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#if HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdlib.h>
+
+#include "dsa.h"
+
+int
+dsa_sha256_verify_digest(const struct dsa_public_key *key,
+			 const uint8_t *digest,
+			 const struct dsa_signature *signature)
+{
+  return _dsa_verify(key, SHA256_DIGEST_SIZE, digest, signature);
+}
+
+int
+dsa_sha256_verify(const struct dsa_public_key *key,
+		  struct sha256_ctx *hash,
+		  const struct dsa_signature *signature)
+{
+  uint8_t digest[SHA256_DIGEST_SIZE];
+  sha256_digest(hash, sizeof(digest), digest);
+
+  return _dsa_verify(key, sizeof(digest), digest, signature);
+}
diff --git a/dsa-sign.c b/dsa-sign.c
index a44c2ea0..9c5a29c9 100644
--- a/dsa-sign.c
+++ b/dsa-sign.c
@@ -5,7 +5,7 @@
 
 /* nettle, low-level cryptographics library
  *
- * Copyright (C) 2002 Niels Möller
+ * Copyright (C) 2002, 2010 Niels Möller
  *  
  * The nettle library is free software; you can redistribute it and/or modify
  * it under the terms of the GNU Lesser General Public License as published by
@@ -27,6 +27,7 @@
 # include "config.h"
 #endif
 
+#include <assert.h>
 #include <stdlib.h>
 
 #include "dsa.h"
@@ -34,17 +35,25 @@
 #include "bignum.h"
 
 
-void
-dsa_sign_digest(const struct dsa_public_key *pub,
-		const struct dsa_private_key *key,
-		void *random_ctx, nettle_random_func random,
-		const uint8_t *digest,
-		struct dsa_signature *signature)
+int
+_dsa_sign(const struct dsa_public_key *pub,
+	  const struct dsa_private_key *key,
+	  void *random_ctx, nettle_random_func random,
+	  unsigned digest_size,
+	  const uint8_t *digest,
+	  struct dsa_signature *signature)
 {
   mpz_t k;
   mpz_t h;
   mpz_t tmp;
-  
+
+  /* Require precise match of bitsize of q and hash size. The general
+     description of DSA in FIPS186-3 allows both larger and smaller q;
+     in the the latter case, the hash must be truncated to the right
+     number of bits. */
+  if (mpz_sizeinbase(pub->q, 2) != 8 * digest_size)
+    return 0;
+
   /* Select k, 0<k<q, randomly */
   mpz_init_set(tmp, pub->q);
   mpz_sub_ui(tmp, tmp, 1);
@@ -59,12 +68,12 @@ dsa_sign_digest(const struct dsa_public_key *pub,
 
   /* Compute hash */
   mpz_init(h);
-  nettle_mpz_set_str_256_u(h, SHA1_DIGEST_SIZE, digest);
+  nettle_mpz_set_str_256_u(h, digest_size, digest);
 
   /* Compute k^-1 (mod q) */
   if (!mpz_invert(k, k, pub->q))
     /* What do we do now? The key is invalid. */
-    abort();
+    return 0;
 
   /* Compute signature s = k^-1 (h + xr) (mod q) */
   mpz_mul(tmp, signature->r, key->x);
@@ -76,18 +85,6 @@ dsa_sign_digest(const struct dsa_public_key *pub,
   mpz_clear(k);
   mpz_clear(h);
   mpz_clear(tmp);
-}
-
-void
-dsa_sign(const struct dsa_public_key *pub,
-	 const struct dsa_private_key *key,
-	 void *random_ctx, nettle_random_func random,
-	 struct sha1_ctx *hash,
-	 struct dsa_signature *signature)
-{
-  uint8_t digest[SHA1_DIGEST_SIZE];
-  sha1_digest(hash, sizeof(digest), digest);
 
-  dsa_sign_digest(pub, key, random_ctx, random,
-		  digest, signature);
+  return 1;
 }
diff --git a/dsa-verify.c b/dsa-verify.c
index 519c4207..faea0a00 100644
--- a/dsa-verify.c
+++ b/dsa-verify.c
@@ -34,16 +34,20 @@
 #include "bignum.h"
 
 int
-dsa_verify_digest(const struct dsa_public_key *key,
-		  const uint8_t *digest,
-		  const struct dsa_signature *signature)
+_dsa_verify(const struct dsa_public_key *key,
+	    unsigned digest_size,
+	    const uint8_t *digest,
+	    const struct dsa_signature *signature)
 {
   mpz_t w;
   mpz_t tmp;
   mpz_t v;
 
   int res;
-  
+
+  if (mpz_sizeinbase(key->q, 2) != 8 * digest_size)
+    return 0;
+
   /* Check that r and s are in the proper range */
   if (mpz_sgn(signature->r) <= 0 || mpz_cmp(signature->r, key->q) >= 0)
     return 0;
@@ -67,7 +71,7 @@ dsa_verify_digest(const struct dsa_public_key *key,
   mpz_init(v);
 
   /* The message digest */
-  nettle_mpz_set_str_256_u(tmp, SHA1_DIGEST_SIZE, digest);
+  nettle_mpz_set_str_256_u(tmp, digest_size, digest);
   
   /* v = g^{w * h (mod q)} (mod p)  */
   mpz_mul(tmp, tmp, w);
@@ -95,14 +99,3 @@ dsa_verify_digest(const struct dsa_public_key *key,
 
   return res;
 }
-
-int
-dsa_verify(const struct dsa_public_key *key,
-	   struct sha1_ctx *hash,
-	   const struct dsa_signature *signature)
-{
-  uint8_t digest[SHA1_DIGEST_SIZE];
-  sha1_digest(hash, sizeof(digest), digest);
-
-  return dsa_verify_digest(key, digest, signature);
-}
diff --git a/dsa.h b/dsa.h
index 32f691de..c98fb12b 100644
--- a/dsa.h
+++ b/dsa.h
@@ -46,10 +46,14 @@ extern "C" {
 #define dsa_private_key_clear nettle_dsa_private_key_clear
 #define dsa_signature_init nettle_dsa_signature_init
 #define dsa_signature_clear nettle_dsa_signature_clear
-#define dsa_sign nettle_dsa_sign
-#define dsa_verify nettle_dsa_verify
-#define dsa_sign_digest nettle_dsa_sign_digest
-#define dsa_verify_digest nettle_dsa_verify_digest
+#define dsa_sha1_sign nettle_dsa_sha1_sign
+#define dsa_sha1_verify nettle_dsa_sha1_verify
+#define dsa_sha256_sign nettle_dsa_sha256_sign
+#define dsa_sha256_verify nettle_dsa_sha256_verify
+#define dsa_sha1_sign_digest nettle_dsa_sha1_sign_digest
+#define dsa_sha1_verify_digest nettle_dsa_sha1_verify_digest
+#define dsa_sha256_sign_digest nettle_dsa_sha256_sign_digest
+#define dsa_sha256_verify_digest nettle_dsa_sha256_verify_digest
 #define dsa_generate_keypair nettle_dsa_generate_keypair
 #define dsa_signature_from_sexp nettle_dsa_signature_from_sexp
 #define dsa_keypair_to_sexp nettle_dsa_keypair_to_sexp
@@ -59,6 +63,8 @@ extern "C" {
 #define dsa_public_key_from_der_iterator nettle_dsa_public_key_from_der_iterator
 #define dsa_openssl_private_key_from_der_iterator nettle_dsa_openssl_private_key_from_der_iterator 
 #define dsa_openssl_private_key_from_der nettle_openssl_provate_key_from_der
+#define _dsa_sign _nettle_dsa_sign
+#define _dsa_verify _nettle_dsa_verify
 
 #define DSA_MIN_P_BITS 512
 #define DSA_Q_OCTETS 20
@@ -138,31 +144,53 @@ void
 dsa_signature_clear(struct dsa_signature *signature);
 
 
-void
-dsa_sign(const struct dsa_public_key *pub,
-	 const struct dsa_private_key *key,
-	 void *random_ctx, nettle_random_func random,
-	 struct sha1_ctx *hash,
-	 struct dsa_signature *signature);
-
-
 int
-dsa_verify(const struct dsa_public_key *key,
-	   struct sha1_ctx *hash,
-	   const struct dsa_signature *signature);
+dsa_sha1_sign(const struct dsa_public_key *pub,
+	      const struct dsa_private_key *key,
+	      void *random_ctx, nettle_random_func random,
+	      struct sha1_ctx *hash,
+	      struct dsa_signature *signature);
 
-void
-dsa_sign_digest(const struct dsa_public_key *pub,
+int
+dsa_sha256_sign(const struct dsa_public_key *pub,
 		const struct dsa_private_key *key,
 		void *random_ctx, nettle_random_func random,
-		const uint8_t *digest,
+		struct sha256_ctx *hash,
 		struct dsa_signature *signature);
 
 int
-dsa_verify_digest(const struct dsa_public_key *key,
-		  const uint8_t *digest,
+dsa_sha1_verify(const struct dsa_public_key *key,
+		struct sha1_ctx *hash,
+		const struct dsa_signature *signature);
+
+int
+dsa_sha256_verify(const struct dsa_public_key *key,
+		  struct sha256_ctx *hash,
 		  const struct dsa_signature *signature);
 
+int
+dsa_sha1_sign_digest(const struct dsa_public_key *pub,
+		     const struct dsa_private_key *key,
+		     void *random_ctx, nettle_random_func random,
+		     const uint8_t *digest,
+		     struct dsa_signature *signature);
+int
+dsa_sha256_sign_digest(const struct dsa_public_key *pub,
+		       const struct dsa_private_key *key,
+		       void *random_ctx, nettle_random_func random,
+		       const uint8_t *digest,
+		       struct dsa_signature *signature);
+
+int
+dsa_sha1_verify_digest(const struct dsa_public_key *key,
+		       const uint8_t *digest,
+		       const struct dsa_signature *signature);
+
+int
+dsa_sha256_verify_digest(const struct dsa_public_key *key,
+			 const uint8_t *digest,
+			 const struct dsa_signature *signature);
+
 /* Key generation */
 
 int
@@ -235,6 +263,21 @@ dsa_openssl_private_key_from_der(struct dsa_public_key *pub,
 				 unsigned length, const uint8_t *data);
 
 
+/* Internal functions. */
+int
+_dsa_sign(const struct dsa_public_key *pub,
+	  const struct dsa_private_key *key,
+	  void *random_ctx, nettle_random_func random,
+	  unsigned digest_size,
+	  const uint8_t *digest,
+	  struct dsa_signature *signature);
+
+int
+_dsa_verify(const struct dsa_public_key *key,
+	    unsigned digest_size,
+	    const uint8_t *digest,
+	    const struct dsa_signature *signature);
+
 #ifdef __cplusplus
 }
 #endif